My most enjoyable use of my Marriott Rewards points was definitely unplanned...
Parents were driving through Alabama in their RV when they experienced engine trouble. They weren't really familar with the Marriott Rewards program beyond knowing I travel extensively for work. They have been homebodies... either at their primary home or their RV home away from home. Probably haven't stayed in a hotel in decades (literally).
Anyway I hooked them up for the night at the Huntsville Marriott. The people on the Platinum line were very nice about arranging a same day reservation and eCertificate stay for one night. Which then turned into two, then five, and ultimately 12 nights as the engine trouble was more extensive than presummed and parts were not available.
The folks at the Huntsville Marriott were super sweet and helpful!! Very friendly from the desk clerks, to housekeeping and the C-lounge attendants. Once they realized my parents were novices, they offered so many ways to help. The littlest things meant so much.... from realizing my parents were sharing one coffee cup because they didn't want to impose on housekeeping to ask for a second ceramic cup for the in room coffee - LOL to managing a tornado watch/warning that sent the entire hotel to the ballroom for safety.
We often plan to use points for some amazing vacation in an exotic locale, but being able to help out a family member who otherwise would have incurred a large unexpected expense is much more enjoyable.